Coexistence Support For Multi-Channel Wireless Communications

ABSTRACT

Systems and techniques relating to wireless communications are described. A described technique includes monitoring a group of wireless channels that are useable by at least a first wireless communication device for wireless communications, receiving one or more beacon signals from one or more second wireless communication devices, identifying, within the group of wireless channels, one or more primary channels on which the one or more beacon signals are received, estimating a traffic load for the one or more identified primary channels, determining, based on the estimated traffic load, whether to use as a primary channel for the first wireless communication device, a channel of the one or more identified primary channels or a channel of the group of wireless channels that is separate from the one or more identified primary channels; and selecting the primary channel for the first wireless communication device based on a result of the determining.

CROSS REFERENCE TO RELATED APPLICATIONS

This present disclosure claims the benefit of the priority of U.S.Provisional Application Ser. No. 61/379,325, filed Sep. 1, 2010 andentitled “VHT COEXISTENCE SUPPORT”; the benefit of the priority of U.S.Provisional Application Ser. No. 61/393,791, filed Oct. 15, 2010 andentitled “VHT COEXISTENCE SUPPORT”; and the benefit of the priority ofU.S. Provisional Application Ser. No. 61/437,159, filed Jan. 28, 2011and entitled “VHT COEXISTENCE SUPPORT.”

This disclosure is related to U.S. patent application Ser. No.12/850,529, filed Aug. 4, 2010, and entitled “SDMA MULTI-DEVICE WIRELESSCOMMUNICATIONS.” This disclosure is related to U.S. patent applicationSer. No. 13/034,409, filed Feb. 24, 2011, and entitled “METHODS ANDAPPARATUS FOR DETERMINING A COMPOSITE CHANNEL.”

All of the applications identified above are incorporated herein byreference in their entirety.

BACKGROUND

This disclosure relates to wireless communication systems, includingWireless Local Area Networks (WLANs).

Wireless communication systems can include multiple wirelesscommunication devices that communicate over one or more wirelesschannels. When operating in an infrastructure mode, a wirelesscommunication device called an access point (AP) provides connectivitywith a network, such as the Internet, to other wireless communicationdevices, e.g., client stations or access terminals (AT). Variousexamples of wireless communication devices include mobile phones, smartphones, wireless routers, and wireless hubs. In some cases, wirelesscommunication electronics are integrated with data processing equipmentsuch as laptops, personal digital assistants, and computers.

Wireless communication systems, such as WLANs, can use one or morewireless communication technologies, such as orthogonal frequencydivision multiplexing (OFDM). In an OFDM based wireless communicationsystem, a data stream is split into multiple data substreams. Such datasubstreams are sent over different OFDM subcarriers, which are commonlyalso referred to as tones or frequency tones. WLANs such as thosedefined in the Institute of Electrical and Electronics Engineers (IEEE)wireless communications standards, e.g., IEEE 802.11a, IEEE 802.11n, orIEEE 802.11ac, can use OFDM to transmit and receive signals.

Wireless communication devices in a WLAN can use one or more protocolsfor a medium access control (MAC) layer and a physical (PHY) layer. Forexample, a wireless communication device can use a Carrier SenseMultiple Access (CSMA) with Collision Avoidance (CA) based protocol fora MAC layer and OFDM for the PHY layer.

Some wireless communication systems use a single-in-single-out (SISO)communication approach, where each wireless communication device uses asingle antenna. Other wireless communication systems use amultiple-in-multiple-out (MIMO) communication approach, where a wirelesscommunication device, for example, uses multiple transmit antennas andmultiple receive antennas. A MIMO-based wireless communication devicecan transmit and receive multiple spatial streams over multiple antennasin each of the tones of an OFDM signal.

SUMMARY

The present disclosure includes systems and techniques for wirelesscommunications.

According to an aspect of the present disclosure, a technique forwireless communications includes monitoring a group of wireless channelsthat are useable by at least a first wireless communication device forwireless communications, receiving one or more beacon signals from oneor more second wireless communication devices, identifying, within thegroup of wireless channels, one or more primary channels on which theone or more beacon signals are received from the one or more secondwireless communication devices, estimating a traffic load for the one ormore identified primary channels, determining, based on the estimatedtraffic load, whether to use as a primary channel for the first wirelesscommunication device a channel of the one or more identified primarychannels or a channel of the group of wireless channels that is separatefrom the one or more identified primary channels, and selecting theprimary channel for the first wireless communication device based on aresult of the determining.

The described systems and techniques can be implemented in electroniccircuitry, computer hardware, firmware, software, or in combinations ofthem, such as the structural means disclosed in this specification andstructural equivalents thereof. This can include at least onecomputer-readable medium embodying a program operable to cause one ormore data processing apparatus (e.g., a signal processing deviceincluding a programmable processor) to perform operations described.Thus, program implementations can be realized from a disclosed method,system, or apparatus, and apparatus implementations can be realized froma disclosed system, computer-readable medium, or method. Similarly,method implementations can be realized from a disclosed system,computer-readable medium, or apparatus, and system implementations canbe realized from a disclosed method, computer-readable medium, orapparatus.

For example, one or more disclosed embodiments can be implemented invarious systems and apparatus, including, but not limited to, a specialpurpose data processing apparatus (e.g., a wireless communication devicesuch as a wireless access point, a remote environment monitor, a router,a switch, a computer system component, a medium access unit), a mobiledata processing apparatus (e.g., a wireless client, a cellulartelephone, a smart phone, a personal digital assistant (PDA), a mobilecomputer, a digital camera), a general purpose data processing apparatussuch as a computer, or combinations of these.

An apparatus for wireless communications can include first circuitryconfigured to monitor a group of wireless channels that are useable byat least a first wireless communication device for wirelesscommunications and to receive one or more beacon signals from one ormore second wireless communication devices. The apparatus can includesecond circuitry configured to identify, within the group of wirelesschannels, one or more primary channels on which the one or more beaconsignals are received from the one or more second wireless communicationdevices, estimate a traffic load for the one or more identified primarychannels, and determine, based on the traffic load, whether to use as aprimary channel for the first wireless communication device either achannel of the one or more identified primary channels or a channel ofthe group of wireless channels that is separate from the one or moreidentified primary channels.

A system for wireless communications can include transceiver electronicsand processor electronics configured to perform operations. Theoperations can include monitoring a group of wireless channels that areuseable by at least a first wireless communication device for wirelesscommunications; receiving, via the transceiver electronics, one or morebeacon signals from one or more second wireless communication devices;identifying, within the group of wireless channels, one or more primarychannels on which the one or more beacon signals are received from theone or more second wireless communication devices; estimating a trafficload for the one or more identified primary channels; determining, basedon the estimated traffic load, whether to use as a primary channel forthe first wireless communication device a channel of the one or moreidentified primary channels or a channel of the group of wirelesschannels that is separate from the one or more identified primarychannels; and selecting the primary channel for the first wirelesscommunication device based on a result of the determining.

These and other implementations can include one or more of the followingfeatures. Selecting the primary channel for the first wirelesscommunication device can include selecting, within the group of wirelesschannels, a channel that is separate from the one or more identifiedprimary channels as the primary channel for the first wirelesscommunication device based on the estimated traffic load exceeding athreshold. Selecting the primary channel for the first wirelesscommunication device can include selecting the primary channel for thefirst wireless communication device from the one or more identifiedprimary channels based on the estimated traffic load not exceeding thethreshold.

Estimating the traffic load can include measuring one or more channelconditions of the one or more identified primary channels, andcalculating one or more busy-to-idle ratios of the one or moreidentified primary channels based on the one or more channel conditions.Determining a primary channel for a device can include comparing the oneor more busy-to-idle ratios with a threshold.

In some implementations, the group of wireless channels includes twofrequency portions, each of the two frequency portions occupying aconsecutive frequency band that is one half of a frequency bandassociated with the group of wireless channels. Selecting the primarychannel for the first wireless communication device can includeselecting a frequency portion of the two frequency portions to be theprimary channel for the first wireless communication device, thefrequency portion having a frequency band separate from one or morefrequency bands of the one or more identified primary channels.

Details of one or more implementations are set forth in the accompanyingdrawings and the description below. Other features and advantages may beapparent from the description and drawings, and from the claims.

DRAWING DESCRIPTIONS

FIG. 1 shows an example of a channel structure for wirelesscommunications.

FIG. 2 shows an example of a wireless network with two wirelesscommunication devices.

FIG. 3 shows an example of a wireless communication device architecture.

FIG. 4 shows an example of a communication process for multi-channelwireless communications.

FIG. 5 shows an example of primary channel selection for a new basicservice set (BSS) in a first BSS coexistence scenario.

FIG. 6 shows an example of primary channel selection for a new BSS in asecond BSS coexistence scenario.

FIG. 7 shows an example of primary channel selection for a new BSS in athird BSS coexistence scenario.

FIG. 8 shows an example of primary channel selection for a new BSS in afourth BSS coexistence scenario.

FIG. 9 shows an example of primary channel selection for a new BSS in afifth BSS coexistence scenario.

FIG. 10 shows an example of primary channel selection for a new BSS in asixth BSS coexistence scenario.

FIG. 11 shows an example of primary channel selection for a new BSS in aseventh BSS coexistence scenario.

FIG. 12 shows an example of primary channel selection for a new BSS inan eighth BSS coexistence scenario.

FIG. 13 shows an example of primary channel selection for a new BSS in aninth BSS coexistence scenario.

FIG. 14 shows an example of primary channel selection for a new BSS in atenth BSS coexistence scenario.

FIG. 15 shows an example of primary channel selection for a new BSS inan eleventh BSS coexistence scenario.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

This disclosure provides details and examples of technologies forwireless local area networks, including systems and techniques forcoexistence support for multi-channel wireless communications. Anexample of a technique for multi-channel device wireless communicationsincludes operating a wireless communication device to communicate in thepresence of other wireless communication devices in a way that increasesfrequency utilization and promotes fairness among devices sharing acommon wireless medium. Potential advantages include an increasedutilization of primary and secondary channel frequency bands, backwardscompatibility with older standards, or both. The techniques andarchitectures presented herein can be implemented in a variety ofwireless communication systems, such as ones based on IEEE 802.11n orIEEE 802.11ac. One of more of the described systems and techniques canbe combined with technology disclosed by U.S. patent application Ser.No. 12/850,529, filed Aug. 4, 2010, and entitled “SDMA MULTI-DEVICEWIRELESS COMMUNICATIONS.”

FIG. 1 shows an example of a channel structure for wirelesscommunications. Wireless communication devices 105, 110 can communicateover a group 120 of channels 125, 130, 135, 140. The group 120 caninclude 20 MHz wireless channel(s), 40 MHz wireless channel(s), 80 MHzwireless channel(s), or 160 MHz wireless channel(s). Other types ofchannels are possible. In some implementations, the channels 125, 130,135, 140 are contiguous. In some implementations, one or more of thechannels 125, 130, 135, 140 are noncontiguous with one or more of theother channels. A device 105, 110 such as an access point (AP), canprovide a basic service set (BSS) for wireless communications. Based onmonitoring the group 120 for activity from an existing BSS from a firstAP 105, a newly activated device (e.g., a second AP 110) can select oneor more channels in the group 120 to provide its own BSS.

In some implementations, the group 120 includes two primary channels125, 135 (referred to as P1 and P2, respectively) and associatedsecondary channels 130, 140 (referred to as S1 and S2, respectively). Atransmission on the P1 channel 125 sets a transmission protection periodsuch as a network allocation vector (NAV) on channels associated withthe group 120. An AP device 105 can communicate with different types ofdevices (e.g., devices based on different standards) such as ahigh-throughout (HT) device (e.g., IEEE 802.11n based device) and a veryhigh-throughout (VHT) device (e.g., IEEE 802.11ac based device). A HTdevice is configured to use the P1 channel 125, the S1 channel 130, or acombination of these, whereas the VHT device is configured to use the P1channel 125, the P2 channel 135, the S1 channel 130, the S2 channel 140,or a combination of two or more of these channels. The AP device 105 canconcurrently transmit to the VHT device and the HT device.

In some cases, an AP device 105 transmits to the VHT device using a P2channel 135 and transmits to the HT device using a P1 channel 125. TheAP device 105 coordinates the transmission of one or more packets on theP1 and P2 channels 125, 135 such that they end at the same time tocreate a window for acknowledgements (ACKs). Moreover, an AP device 105can use the P1 channel 125 and the S1 channel 130 to provide a 40 MHzwide transmission to a HT device and use the P2 channel 135 and the S2channel 140 to provide a 40 MHz wide transmission to a VHT device. Insome cases, the AP device 105 can use all of the channels of the group120 to communicate with a single device.

An access point, such as AP device 105, can transmit packets to twodevices for respective overlapping transmission periods. The two devicescan implement different respective wireless communication standards(e.g., IEEE 802.11n or IEEE 802.11ac). For example, transmitting a firstpacket can include transmitting to a first wireless communication devicethat is configured for communications based on a first wirelesscommunication standard (e.g., IEEE 802.11n), whereas, transmitting asecond packet can include transmitting to a second wireless device thatis configured for communications based on a second wirelesscommunication standard (e.g., IEEE 802.11ac). Note that the first andthe second wireless communication standards can define mutuallycompatible communications on the first channel, with the second standarddefining communications for the first and second channels. In somecases, an access point can have overlapping transmissions to the samedevice using multiple channels. For example, transmitting first andsecond packets can include transmitting the packets concurrently to thesame device.

FIG. 2 shows an example of a wireless network with two wirelesscommunication devices. Wireless communication devices 205, 207 such asan access point (AP), base station (BS), wireless headset, accessterminal (AT), client station, or mobile station (MS) can includecircuitry such as processor electronics 210, 212. Processor electronics210, 212 can include one or more processors that implement one or moretechniques presented in this disclosure. Wireless communication devices205, 207 include circuitry such as transceiver electronics 215, 217 tosend and receive wireless signals over one or more antennas 220 a, 220b, 222 a, 222 b. In some implementations, transceiver electronics 215,217 include integrated transmitting and receiving circuitry. In someimplementations, transceiver electronics 215, 217 include multiple radiounits. In some implementations, a radio unit includes a baseband unit(BBU) and a radio frequency unit (RFU) to transmit and receive signals.Transceiver electronics 215, 217 can include one or more of: detector,decoder, modulator, and encoder. Transceiver electronics 215, 217 caninclude one or more analog circuits. Wireless communication devices 205,207 include one or more memories 225, 227 configured to storeinformation such as data, instructions, or both. In someimplementations, wireless communication devices 205, 207 includededicated circuitry for transmitting and dedicated circuitry forreceiving. In some implementations, a wireless communication device 205,207 is operable to act as a serving device (e.g., an access point), or aclient device.

In some implementations, a first wireless communication device 205 cantransmit data to one or more devices via two or more spatial wirelesscommunication channels such as orthogonal spatial subspaces, e.g.,orthogonal Space Division Multiple Access (SDMA) subspaces. For example,the first wireless communication device 205 can concurrently transmitdata to a second wireless communication device 207 using a spatialwireless channel and can transmit data to a third wireless communicationdevice (not shown) using a different spatial wireless channel. In someimplementations, the first wireless communication device 205 implementsa space division technique to transmit data to two or more wirelesscommunication devices using two or more spatial multiplexing matrices toprovide spatially separated wireless channels in a single frequencyband.

Wireless communication devices, such as a MIMO enabled access point, cantransmit signals for multiple client wireless communication devices atthe same time in the same frequency band by applying one or moretransmitter side beam forming matrices to spatially separate signalsassociated with different client wireless communication devices. Basedon different signal patterns at the different antennas of the wirelesscommunication devices, each client wireless communication device candiscern its own signal. A MIMO enabled access point can participate insounding to obtain channel state information for each of the clientwireless communication devices. The access point can compute spatialmultiplexing matrices, such as spatial steering matrices, based on thedifferent channel state information to spatially separate signals todifferent client devices.

FIG. 3 shows an example of a wireless communication device architecture,which can be used in the various implementations described above. Awireless communication device 350 can produce signals for two or moreclients in two or more frequency bands. Note that a channel can beassociated with a frequency band. A frequency band can include a groupof OFDM sub-carriers. The wireless communication device 350 includes aMAC module 355. The MAC module 355 can include one or more MAC controlunits (MCUs) (not shown). The wireless communication device 350 includesthree or more encoders 360 a, 360 b, 360 c that receive data streams,from the MAC module 355, which are associated with one or more clients(e.g., N clients, or N transmission streams to one or more clients). Theencoders 360 a, 360 b, 360 c can perform encoding, such as a forwarderror correction (FEC) encoding technique to produce respective encodedstreams. Modulators 365 a, 365 b, 365 c can perform modulation onrespective encoded streams to produce modulated streams to an OrthogonalFrequency-Division Multiple Access (OFDMA) Inverse Fast FourierTransform (IFFT) module 380.

The OFDMA IFFT (O-IFFT) module 380 can perform IFFTs on modulatedstreams from respective modulators 365 a, 365 b, 365 c. In someimplementations, the O-IFFT module 380 can include an OFDMA module andan IFFT module, where the OFDMA module maps different modulated streamsto different subcarrier groups before IFFT processing. In someimplementations, the O-IFFT module 380 can perform an IFFT on an outputof the first modulator 365 a to produce a first time domain signalassociated with a first frequency band. The O-IFFT module 380 canperform an IFFT on an output of the second modulator 365 b to produce asecond time domain signal associated with a second frequency band. TheO-IFFT module 380 can perform an IFFT on an output of the Nth modulator365 c to produce an Nth time domain signal associated with an Nthfrequency band.

In some implementations, the O-IFFT module 380 can combine the frequencycomponents, e.g., frequency band components, associated with the outputof respective first modulators 365 a, 365 b, 365 c. The O-IFFT module380 can perform an IFFT on the combination to produce a time domainsignal associated with the frequency bands. In some implementations, anO-IFFT module 380 is configured to use one or more FFT bandwidthfrequencies, e.g., 20 MHz, 40 MHz, 80 MHz, and 160 MHz. In someimplementations, the O-IFFT module 380 can perform different IFFTs.

A digital filtering and radio module 385 can filter the time domainsignal and amplify the signal for transmission via an antenna module390. An antenna module 390 can include multiple transmit antennas andmultiple receive antennas. In some implementations, an antenna module390 is a detachable unit that is external to a wireless communicationdevice 350.

In some implementations, a wireless communication device 350 includesone or more integrated circuits (ICs). In some implementations, a MACmodule 355 includes one or more ICs. In some implementations, a wirelesscommunication device 350 includes an IC that implements thefunctionality of multiple units and/or modules such as a MAC module,MCU, BBU, or RFU. In some implementations, a wireless communicationdevice 350 includes a host processor that provides a data stream to aMAC module 355 for transmission. In some implementations, a wirelesscommunication device 350 includes a host processor that receives a datastream from the MAC module 355. In some implementations, a hostprocessor includes a MAC module 355.

FIG. 4 shows an example of a communication process for multi-channelwireless communications. At 405, a communication process monitors agroup of wireless channels that are usable by at least a first wirelesscommunication device for wireless communications. The first wirelesscommunication device can be a VHT device (e.g., IEEE 802.11ac baseddevice). The group of wireless channels can be in the 5 GHz band,including a 20 MHz primary channel (P), a 20 MHz secondary channel (S1),and a 40 MHz secondary channel (S2). In some implementations, the groupof wireless channels can also include an 80 MHz secondary channel (S3)in addition to the P, S1 and S2. In some implementations, thecombination of P and S1 can be a 40 MHz channel as defined in an IEEE802.11n standard. The combination of P, S1 and S2 can be an 80 MHzchannel including two adjacent 40 MHz channels as defined in an IEEE802.11n standard. The S3 can also include two adjacent 40 MHz channelsas defined in an IEEE 802.11n standard. When the frequency allocation ofP is determined, the frequency allocations of other secondary channelsin the group of wireless channels are also determined. In someimplementations, for each 20 MHz sub-channel in the group of wirelesschannels, clear channel assessment technique can be used to monitor thegroup of wireless channels for channel conditions and/or traffic loads.

At 410, the communication process receives one or more beacon signalsfrom one or more second wireless communication devices. The one or moresecond wireless communication devices can be devices such as HT devices(e.g., IEEE 802.11n based devices), VHT devices (e.g., IEEE 802.11acbased devices), or both.

At 415, the communication process identifies, within the group ofwireless channels, one or more primary channels on which the one or morebeacon signals are received. For example, the one or more primarychannels can be one or more 20 MHz primary channels for one or morecorresponding IEEE 802.11n basic service sets.

At 420, the communication process estimates a traffic load for the oneor more identified primary channels. In some implementations, thetraffic load can be estimated based on energy detection of the one ormore identified primary channels. In some implementations, thecommunication process can also calculate a busy-to-idle ratio of the oneor more identified primary channels, based on measuring channelconditions of the one or more identified primary channels. Then thecommunication process can determine, based on the calculatedbusy-to-idle ratio, a traffic threshold of the one or more identifiedprimary channels.

At 425, the communication process determines, based on the estimatedtraffic load, whether to use as a primary channel for the first wirelesscommunication device a channel of the one or more identified primarychannels or a channel of the group of wireless channels that is separatefrom the one or more identified primary channels. The determining at 425can include comparing the busy-to-idle ratio with a threshold to producea comparison result.

At 430, the communication process selects the primary channel for thefirst wireless communication device based on a result of the determiningat 425. Selecting the primary channel for the first wirelesscommunication device can include selecting, within the group of wirelesschannels, a channel that is separate from the one or more identifiedprimary channels as the primary channel for the first wirelesscommunication device based on the estimated traffic load exceeding athreshold. Furthermore, selecting the primary channel for the firstwireless communication device can include selecting the primary channelfor the first wireless communication device from the one or moreidentified primary channels based on the estimated traffic load notexceeding the threshold.

In some implementations, the group of wireless channels includes twofrequency portions; each of the two frequency portions occupies aconsecutive frequency band that is one half of a frequency bandassociated with the group of wireless channels. Selecting the primarychannel for the first wireless communication device can includeselecting a frequency portion of the two frequency portions to be theprimary channel for the first wireless communication device, thefrequency portion having a frequency band separate from one or morefrequency bands of the one or more identified primary channels.

In some cases, the one or more beacon signals are received from onesecond wireless communication device. Selecting the primary channel forthe first wireless communication device can include selecting a channelon which the one or more beacon signals are received as the primarychannel for the first wireless communication device, where the selectedchannel is a primary channel of a second communication device.

In some cases, at least a subset of the group of wireless channels doesnot overlap with wireless channels that are usable by the one or moresecond wireless communication devices. Selecting the primary channel forthe first wireless communication device can include selecting a channelin the subset of the group of wireless channels as the primary channelfor the first wireless communication device.

In some implementations, the one or more second wireless communicationdevices include a device that uses a 20 MHz primary channel, a 20 MHzsecondary channel, and a 40 MHz secondary channel. Selecting the primarychannel for the first wireless communication device can includeselecting a channel in the 40 MHz secondary channel as the primarychannel for the first wireless communication device.

In some implementations, the one or more second wireless communicationdevices include a device that uses a 20 MHz primary channel, a 20 MHzsecondary channel, a 40 MHz secondary channel, and an 80 MHz secondarychannel. Selecting the primary channel for the first wirelesscommunication device can include selecting a channel in the 80 MHzsecondary channel as the primary channel for the first wirelesscommunication device.

In some implementations, when the one or more beacons are detected in a20 MHz channel, the communication process can deem the 20 MHz channel asthe identified primary channel for a second wireless communicationdevice. The communication process can select the identified primarychannel of the second wireless communication device as the primarychannel for the first wireless communication device. For example, a VHTAP (e.g., the first wireless communication device), operable in thecommunication process, can start an 80 MHz or 160 MHz BSS (80/160 BSS)by selecting a primary channel that overlaps with an existing primarychannel (e.g., the identified primary channel for the second wirelesscommunication device). When the one or more beacons are detected inmultiple 20 MHz channels (e.g., multiple primary channels areidentified), the communication process can select a channel from themultiple identified primary channels as the primary channel for thefirst wireless communication device. For example, a VHT AP that isconfigured to perform the communication process can start an 80/160 BSSby selecting a primary channel that overlaps with one of the multipleexisting primary channels that are being used by other devices. The VHTAP can further select a primary channel of the 80/160 BSS to overlapwith the least busy channel of the existing primary channels. In somecases, the communication process can select a channel that does notoverlap with the wireless channels used by the one or more secondcommunication devices.

In some implementations, when there is an existing 80 MHz BSS, thecommunication process can select a 20 MHz channel in the S2 (e.g., a 40MHz secondary channel) of the existing 80 MHz BSS as its primarychannel. When there is an existing 160 MHz BSS, the communicationprocess can select a 20 MHz channel in the S3 (e.g., an 80 MHz secondarychannel) of the existing 160 MHz BSS as its primary channel. Additionalexamples of selecting the primary channel for the first wirelesscommunication are described in connection with FIGS. 5-15 with respectto different BSS existence scenarios.

FIG. 5 shows an example of primary channel selection for a new BSS in afirst BSS coexistence scenario. There is an existing BSS 520 (e.g., anIEEE 802.11n based BSS) that uses a 40 MHz frequency band. The existingBSS 520 is provided by an existing device. Also, there is a new BSS 510(e.g., an IEEE 802.11ac based BSS) 510 that uses an 80 MHz frequencyband. The new BSS 510 is provided by a newly activated device (e.g.,turned on, restarted, etc.). In this example, the new 80 MHz BSS 510includes channels 515A, 515B that overlap with the 20 MHz primarychannel 525A and the 20 MHz secondary channel 525B of the existing 40MHz BSS 520.

The primary channel for the newly activated device can be selected suchthat the new BSS 510 has increased chances for obtaining a transmissionopportunity (TXOP). To obtain a TXOP, a device such as an AP in the BSScan monitor one or more primary channels and one or more secondarychannels for wireless traffic. If a primary channel has been idle for anArbitration InterFrame Space (AIFS) plus a back-off duration, and one ormore secondary channels have been idle for at least a Point coordinationfunction InterFrame Space (PIFS) duration, the device can use the idlechannels for the TXOP. Based on obtaining a TXOP, the device can sendone or more frames continuously with a Short InterFrame Space (SIFS)duration gap between the frames.

The first option shown in FIG. 5 for primary channel selection for thenew BSS 510 is as follows. The primary channel of the new BSS 510 can beselected from one of the channels 515C, 515D that do not overlap withthe channels 525A, 525B used by the existing BSS 520. In someimplementations, the primary channel of the new BSS 510 includes both ofthe channels 515C, 515D. The new BSS 510 can access channels 515C and515D without contention from the existing BSS 520. The existing BSS 520can access channels 525A and 525B most of the time, and it wouldexperience some contention from the new BSS 510. The new BSS 510 canaccess channels 515A and 515B during a vulnerable period, which is atime period that includes the backoff time duration and/or a channelaccess delay (e.g., PIFS) of the existing BSS 520. When the idlestarting time (or the backoff starting time) of the new BSS 510 fallsinto the vulnerable period, the new BSS 510 can use the channels 515Aand 515B. In some implementations, When the vulnerable period is muchless than the TXOP duration of the new BSS 510, the chance for the newBSS 510 to access the channels used by the existing BSS 520 channels canbe low. With respect to the traffic loads of the channels, when both thenew BSS 510 and the existing BSS 520 are fully loaded (e.g.,experiencing a channel utilization rate of greater than 90%, othernumerical values are possible), all the channels can be fully utilized.When the new BSS 510 is fully loaded and the existing BSS 520 is lightlyloaded, the new BSS 510 can have sufficient usage of channels 515C and515D, and can gain some usage of channels 515A, 515B, or both. When thenew BSS 510 is lightly loaded and the existing BSS 520 is fully loaded,the new BSS 510 can avoid using channels 515A, 515B, or both.

The second option shown in FIG. 5 for primary channel selection for thenew BSS 510 is as follows. The primary channel 515B of the new BSS 510can be selected to overlap with the primary channel 525A of the existingBSS 520. Based on this option, the new BSS 510 can share the usage of515B with the existing BSS 520, and the new BSS 510 can access channels515C and 515D when it gains access to channel 515B. With respect to thetraffic loads of the channels, when the new BSS 510 is fully loaded, itcan gain access to channels 515C and 515D if the new BSS 510 has a TXOP.When the new BSS 510 is lightly loaded and the existing BSS 520 is fullyloaded, the new BSS 510 can compete with the existing BSS 520 foraccessing channel 515B.

The third option shown in FIG. 5 for primary channel selection for thenew BSS 510 is as follows. The primary channel 515A of the new BSS 510can be selected to overlap with the secondary channel 525B of theexisting BSS 520. Based on this option, the new BSS 510 can share theusage of channel 515B with the existing BSS 520, and the new BSS 510 canaccess channels 515C and 515D when it gains access to channel 515B. Withrespect to the traffic loads of the channels, when both BSS's are fullyloaded, the new BSS 510 can compete with the existing BSS 520 foraccessing their primary channel. When the new BSS 510 is fully loadedand the existing BSS 520 is lightly loaded, the new BSS 510 can gainmore access to channels 525A and 525B. In some implementations, if thenew BSS 510 cannot access 515B, then it also cannot access channels 515Cand 515D.

In some implementations, the new BSS 510 is fully loaded and theexisting BSS is lightly loaded, the existing BSS may use the secondoption for primary channel selection. Otherwise, the new existing BSS510 may use the first option for the primary channel selection. Theprimary channel selection can be changed by an AP of the new BSS 510 ifthe traffic conditions of the new BSS 510 and/or the existing BSS 520change.

FIG. 6 shows an example of primary channel selection for a new BSS in asecond BSS coexistence scenario. There are two existing BSS's 610, 630(e.g., IEEE 802.11n based BSS's), each use a 40 MHz frequency band. Theexisting BSS's 610, 630 are provided by existing devices. Also, there isa new BSS 620 (e.g., an IEEE 802.11ac based BSS) that uses an 80 MHzfrequency band. In this example, the new BSS 620 (80 MHz) includeschannels 625C, 625D that overlap with the primary channel 615A and thesecondary channel 615B of the existing BSS 610. The channels 625C, 625Dalso overlap with the primary channel 635A and secondary channel 635B ofthe existing BSS 630. Furthermore, the primary channel 615A of theexisting BSS 610 does not overlap with the primary channel 635A of theexisting BSS 630.

The first option shown in FIG. 6 for primary channel selection for thenew BSS 620 is as follows. The primary channel (625B or 625A) of the newBSS 620 can be selected from one of the channels 625A, 625B that do notoverlap with the primary channels 615A, 635A and secondary channels 615Band 635B used by the existing BSS's 610, 630. Based on this option, thenew BSS 620 can access channels 625A and 625B without contention fromthe existing BSS's 610, 630. The existing BSS's 610, 630 can accesschannels 625C and/or 625D most of the time, since they would experiencesome contention from the new BSS 620. With respect to the traffic loadsof the channels, when all the BSS's are fully loaded, all the channelscan be fully utilized. When the new BSS 620 is fully loaded, and boththe existing BSS's are lightly loaded, the new BSS 620 can havesufficient usage of channels 625A and 625B, and can gain some usage ofchannels 625C and 625D. When the new BSS 620 is lightly loaded and theexisting BSS's are fully loaded, the existing BSS's 610, 630 can havemost of the usage of channels 625C and 625D.

The second option shown in FIG. 6 for primary channel selection for thenew BSS 620 is as follows. The primary channel 625C of the new BSS 620can be selected to overlap with the least busy existing primary channelbetween the primary channel 615A and the primary channel 635A. The newBSS 620 can share the usage of channel 625C with the least busy existingBSS. The new BSS 620 can access channels 625A and 625B when it gainsaccess to channels 625C and 625D. With respect to the traffic loads ofthe channels, when all the BSS's are fully loaded, the new BSS 620 canshare channel 625C with existing BSS's 610, 630. When the new BSS 620 isfully loaded and the existing BSS's 610, 630 are lightly loaded, the newBSS 620 can have most of the usage of channels 625C, and some usage ofchannels 625A, 625B, and 625D.

The third option shown in FIG. 6 for primary channel selection for thenew BSS 620 is as follows. The primary channel 625D of the new BSS 620can be selected to overlap with a busy existing BSS's primary channel.

In some implementations, for any traffic loads of the new BSS 620 andthe existing BSS's 610, 630, the new BSS 620 can use the first option toselect the primary channel. The third option may be chosen when thefirst and the second options are not available.

FIG. 7 shows an example of primary channel selection in a third BSScoexistence scenario. There are two existing BSS's 720, 730 (e.g., IEEE802.11n based BSS's), where each uses a 40 MHz frequency band. Theexisting BSS's 720, 730 are provided by existing devices. There is alsoa new BSS 710 (e.g., an IEEE 802.11ac based BSS) that uses an 80 MHzfrequency band. The two 40 MHz frequency bands used by the two existingBSS's 720, 730 are adjacent to each other, and the concatenation of thetwo 40 MHz frequency band overlaps with the 80 MHz frequency band of thenew BSS 710. The existing BSS A 720 uses a 20 MHz primary channel 725Aand a 20 MHz secondary channel 725B, and the existing BSS B 730 uses a20 MHz primary channel 735A and a 20 MHz secondary channel 735B.Furthermore, the primary channel 725A of the existing BSS A 720 isbusier than the primary channel 735A of the existing BSS B 730. In otherwords, the traffic load on the primary channel 725A of existing BSS A720 is higher than the traffic load on the primary channel 735A ofexisting BSS B 730.

The first option shown in FIG. 7 for primary channel selection for thenew BSS 710 is as follows. The primary channel 715A of the new BSS 710can be selected to overlap with the least busy primary channel 735A ofexisting BSS B 730. Based on option 1, the new BSS 710 can share 715Aand 715B with a less busy BSS B 730 and get more usage of 715A and 715B.

The second option shown in FIG. 7 for primary channel selection for thenew BSS 710 is as follows. The primary channel 715B of the new BSS 710can be selected to overlap with secondary channel 735B associated withthe least busy primary channel 735A. Based on this option, the new BSS710 can get more usage of channel 715B and some usage of channel 715A.

The third option shown in FIG. 7 for primary channel selection for thenew BSS 710 is as follows. The primary channel (715C or 715D) can beselected to overlap with a busy primary channel 725A of the existing BSSA 720. Based on this option, the new BSS 710 can share channels 715C and715B with the busy existing BSS A 720 and can get a fair share ofchannels 715C and 715D. The new BSS 710 can also get some usage ofchannels 715A and 715B when it obtains 715A and 715B.

The fourth option shown in FIG. 7 for primary channel selection for thenew BSS 710 is as follows. The primary channel of the new BSS 710 can beselected to overlap with the secondary channel 725B associated with thebusy primary channel 725A of existing BSS A 720. Based on this option,the new BSS 710 can get most of the usage of channel 715D.

In some implementations, for any traffic loads of the new BSS 710 andthe existing BSS's 720, 730, the new BSS 710 can use the first option toselect the primary channel.

FIG. 8 shows an example of primary channel selection in a fourth BSScoexistence scenario. There is an existing BSS 820 (e.g., an IEEE802.11ac based BSS) that uses an 80 MHz frequency band. The existing BSS820 is provided by an existing device. There is also a new BSS 810(e.g., an IEEE 802.11ac based BSS) that uses an 80 MHz frequency bandthat overlaps with the 80 MHz frequency band of the existing BSS 820.The new BSS 810 is provided by a new device. In this example, theexisting BSS includes a primary channel 825A that is busy, a firstsecondary channel 825B which can be referred to as S1, and a secondsecondary channel 825C (which can be referred to as S2), and a thirdsecondary channel 825D (which can be referred to as S3).

The first option shown in FIG. 8 for primary channel selection for thenew BSS 810 is as follows. The primary channel (channel 815A, channel815B, or both) of the new BSS 810 can be selected to at least partiallyoverlap with the S2 and S3 channels 825C, 825D of the existing BSS 820.Based on this option, the new BSS 810 can access channels 815A, 815Bwithout contention from the existing BSS 820, and can access channels815C, 815D most of the time with some contention from the exiting BSS820. With respect to the traffic loads of the channels, when both BSS's810, 820 are fully loaded, all the channels can be fully utilized. Whenthe new BSS 810 is fully loaded and the existing BSS 820 is lightlyloaded, the new BSS 810 can have sufficient usage of channels 815A and815B, and can gain some usage of channels 815C and 815D. When the newBSS 810 is lightly loaded and the existing BSS 820 is fully loaded, theexisting BSS 820 can have sufficient usage of channels 810C and 810D,and can gain some usage of channels 815A and 815B.

The second option shown in FIG. 8 for primary channel selection for thenew BSS 810 is as follows. The primary channel 815C of the new BSS 810can be selected to overlap with the primary channel 825A of the existingBSS 820. Based on this option, the new BSS 810 can share the usage ofchannel 815C with the existing BSS 820. The new BSS 810 can accesschannels 815A and 815B when it gains access to channels 815C and 815D.With respect to the traffic loads of the channels, when both BSS's arefully loaded, channels 815A and 815B can be fully utilized. When the newBSS 810 is fully loaded and the existing BSS 820 is lightly loaded, allthe channels can be sufficiently used. When the new BSS 810 is lightlyloaded and the existing BSS 820 is fully loaded, all the channels can besufficiently used.

The third option shown in FIG. 8 for primary channel selection for thenew BSS 810 is as follows. The primary channel 815D of the new BSS 810can be selected to overlap with secondary channel 825B of the existingBSS 820. Based on this option, the existing BSS 820 can access channel815C most of the time with some contention from the new BSS 810. The newBSS 810 can access channel 815D most of the time with some contentionfrom the existing BSS 820. One of the BSS's 810, 820 can access all thechannels when it can access the other BSS's primary channel. When bothBSS's are fully loaded, the new BSS 810 can have sufficient usage ofchannel 815D, and the existing BSS 820 can have sufficient usage ofchannel 815C. When the new BSS 810 is fully loaded and the existing BSS820 is lightly loaded, the new BSS 810 can gain some access of channels815A-C. When the new BSS 810 is lightly loaded and the existing BSS 820is fully loaded, the existing BSS 820 can gain some access of channel815D.

In some implementations, when both BSS's are fully loaded, the new BSS810 can use the first to select primary channel. Otherwise, the new BSS810 can use the second option to select primary channel.

FIG. 9 shows an example of primary channel selection for a new BSS in afifth BSS coexistence scenario. There is an existing BSS 910 (e.g., anIEEE 802.11n based BSS) that uses a 40 MHz frequency band, and anexisting BSS 930 (e.g., IEEE 802.11ac based BSS) 930 that uses an 80 MHzfrequency band. The existing BSS's 910, 930 are provided by existingdevices. There is also a new BSS 920 (e.g., an IEEE 802.11ac based BSS)that uses an 80 MHz frequency band. The new BSS 920 is provided by a newdevice. The frequency band of the existing BSS 930 (80 MHz) overlapswith the frequency band used by the new BSS 920. The frequency band ofthe existing BSS 910 (40 MHz) partially overlaps with the new BSS 920and the existing BSS 930 (80 MHz). Furthermore, the primary channel 915Aof the existing BSS 910 (40 MHz) overlaps with the primary channel 935Aof the existing BSS 930 (80 MHz).

The first option shown in FIG. 9 for primary channel selection for thenew BSS 920 is as follows. The primary channel (925A or 925B) of the newBSS can be selected to partially overlap with S2 (935C and 935D) of theexisting BSS 930. Based on this option, the new BSS 920 can access 925Aand 925B without any contention from both existing BSS's 910, 930. Theexisting BSS's 910, 930 can access 925C and 925D most of the time withsome contention from the new BSS 920. With respect to the traffic loadsof the channels, when both BSS's are fully loaded, all the channels canbe fully utilized, when the new BSS 920 is fully loaded and the existingBSS's 910, 930 are lightly loaded, the new BSS 920 can make sufficientusage of channels 925A and 925B, and can gain some usage of channels925C and 925D. When the new BSS 920 is lightly loaded and the existingBSS's 910, 930 are fully loaded, the existing BSS's 910, 930 can makesufficient usage of channels 925C and 925D, and can gain some usage ofchannels 925A and 925B

The second option shown in FIG. 9 for primary channel selection for thenew BSS 920 is as follows. The primary channel 925C of the new BSS 920can be selected to overlap with the primary channels 915A, 935A of theexisting BSS's 910, 930, respectively. Based on this option, the new BSS920 can share the usage of channel 925C with the existing BSS's 910,930. The new BSS 920 can access channels 925A and 925B when it gainsaccess to channels 925C and 925D. With respect to the traffic loads ofthe channels, when the new BSS 920 is fully loaded and the existingBSS's 910, 930 are lightly loaded, all the channels can be sufficientlyused. When the new BSS 920 is lightly loaded and the existing BSS's 910,930 are fully loaded, all the channels can be sufficiently used.

The third option shown in FIG. 9 for primary channel selection for thenew BSS 920 is as follows. The primary channel 925D of the new BSS 920can be selected to overlap with the secondary channels 915B, 935B of therespective existing BSS's 910, 930.

In some implementations, when both existing BSS's 910, 930 are fullyloaded, the new BSS 920 can select its primary channel according to thefirst option. Otherwise, the new BSS 920 can select its primary channelaccording to the second option. The third option can be chosen when thefirst and the second options are not available.

FIG. 10 shows an example of primary channel selection for a new BSS in asixth BSS coexistence scenario. There is a first existing BSS 1010(e.g., an IEEE 802.11n based BSS) that uses a 40 MHz frequency band.Also, there is second existing BSS 1030 (e.g., IEEE 802.11ac based BSS)that uses an 80 MHz frequency band. The existing BSS's 1010, 1030 areprovided by existing devices. There is a new BSS 1020 (e.g., an IEEE802.11ac based BSS) that uses an 80 MHz frequency band. The frequencyband of the existing BSS 1030 (80 MHz) overlaps with the frequency bandof the new BSS 1020. The frequency band of the existing BSS 1010 (40MHz) partially overlaps with the new BSS 1020 and the existing BSS 1030(80 MHz). The primary channel 1015A of the existing BSS 1010 (40 MHz)and the primary channel 1035A of the existing BSS 1030 (80 MHz) arelocated separately in two different 40 MHz portions.

The first option shown in FIG. 10 for primary channel selection for thenew BSS 1020 is as follows. The primary channel 1025A of the new BSS1020 can be selected to overlap with the primary channel 1035A of theexisting 80 MHz BSS 1030. Based on this option, the new BSS 1020 canshare channels 1025A and 1025B with the existing 80 MHz BSS 1030. Withrespect to the traffic loads of the channels, when all the BSS's arefully loaded, all the channels can be sufficiently utilized. Theexisting 40 MHz BSS 1010 can make sufficient use of channels 1025C and1025D. The two 80 MHz BSS's 1020, 1030 can share channels 1025A and1025B. When the new BSS 1020 is fully loaded and the existing BSS's1010, 1030 are lightly loaded, the new BSS 1020 can have most of theusage of channels 1025A and 1025B with some contention from existingBSS's 1010, 1030, and can gain some usage of channels 1025C and 1025D.When the new BSS 1020 is lightly loaded, and the existing BSS's 1010,1030 are fully loaded, the existing 40 MHz BSS 1010 can have sufficientusage of channels 1025C and 1025D, and the existing 80 MHz BSS 1030 cangain some usage of channels 1025A and 1025B

The second option shown in FIG. 10 for primary channel selection for thenew BSS 1020 is as follows. The primary channel 1025C of the new BSS1020 can be selected to overlap with the primary channel 1015A of the 40MHz existing BSS 1010. Based on this option, the new BSS 1020 can sharechannels 1025C and 1025D with the 40 MHz existing BSS 1010. With respectto the traffic loads of the channels, when all the BSS's are fullyloaded, the 80 MHz existing BSS 1030 can sufficiently use channels 1025Aand 1025B, and the new BSS 1020 can share channels 1025C and 1025D withthe 40 MHz BSS 1010. When the new BSS 1020 is fully loaded and existingBSS's 1010, 1030 are lightly loaded, the new BSS 1020 can gain most ofthe usage of channels 1025C and 1025D with some contention from theexisting BSS's 1010, 1030. The new BSS 1020 can gain some usage ofchannels 1025A and 1025B. When the new BSS 1020 is lightly loaded, andthe existing BSS's 1010, 1030 are fully loaded, the existing 40 MHz BSS1010 can have sufficient usage of its channels 1015A, 1015B.

The third option shown in FIG. 10 for primary channel selection for thenew BSS 1020 is as follows. The primary channel 1025B of the new BSS1020 can be selected to overlap with secondary channel 1035B of theexisting 80 MHz BSS 1030.

The fourth option shown in FIG. 10 for primary channel selection for thenew BSS 1020 is as follows. The primary channel 1025D of the new BSS1020 can be selected to overlap with secondary channel 1015B of the 40MHz existing BSS 1010 and the secondary channel 1035D of the existing 80MHz BSS 1030. The secondary channel 1035 is a 20 MHz portion of S21035C, 1035D of the existing 80 MHz BSS 1030.

In some implementations, the new BSS 1020 can select its primary channelaccording to the first option if the traffic load of the 40 MHz existingBSS 1010 is heavier than the existing 80 MHz existing BSS 1030.Otherwise, the new BSS 1020 can select its primary channel according tothe second option. The new BSS 1020 can select its primary channelaccording to the third and fourth options when the first and the secondoptions are not available.

FIG. 11 shows an example of primary channel selection for a new BSS in aseventh BSS coexistence scenario. There is an existing BSS 1110 (e.g.,an IEEE 802.11n based BSS) that uses a 40 MHz frequency band, and anexisting BSS 1130 (e.g., IEEE 802.11ac based BSS) that uses an 80 MHzfrequency band. The existing BSS's 1110, 1130 are provided by existingdevices. There is also a new BSS 1120 (e.g., an IEEE 802.11ac based BSS)that uses an 80 MHz frequency band. The frequency band of the existingBSS 1130 (80 MHz) overlaps with the frequency band of the new BSS 1120.The frequency band of the existing BSS 1110 (40 MHz) partially overlapswith the new BSS 1120 and the existing BSS 1130 (80 MHz). The primarychannel 1115A of the existing BSS 1110 (40 MHz) and the primary channel1035A of the existing BSS 1130 (80 MHz) are located in a same 40 MHzportion, but do not overlap with each other.

The first option shown in FIG. 11 for primary channel selection for thenew BSS 1120 is as follows. The primary channel (channel 1125A orchannel 1125B) of the new BSS 1120 can be selected to overlap with oneor both of the secondary channels 1135C, 1135D of the existing BSS 1130.Based on this option, the new BSS 1120 can access channels 1125A and1125B without contention from the existing BSS's 1110, 1130. Theexisting BSS's 1110, 1130 can access the frequency band associated withchannels 1125C, 1125D most of the time. With respect to the trafficloads of the channels, when all the BSS's 1110, 1120, 1130 are fullyloaded, all the channels can be sufficiently utilized. When the new BSS1120 is fully loaded and the existing BSS's 1110, 1130 are lightlyloaded, the new BSS 1120 can sufficiently use channels 1125A and 1125B,and can gain some usage of channels 1125C and 1125D. When the new BSS1120 is lightly loaded and the existing BSS's 1110, 1130 are fullyloaded, the existing BSS's 1110, 1130 can sufficiently use theirchannels that overlap with channels 1125C and 1125D of the new BSS 1120.

The second option shown in FIG. 11 for primary channel selection for thenew BSS 1120 is as follows. The primary channel 1125C of the new BSS1120 can be selected to overlap with the primary channel 1135A of the 80MHz existing BSS 1130 and S1 1115 of the 40 MHz existing BSS 1110. Basedon this option, the new BSS 1120 can share the usage of channel 1125Cwith the 80 MHz BSS 1130. The new BSS 1120 can access channels 1125A and1125B when it gains access to channels 1125C and 1125D. With respect tothe traffic loads of the channels, when all the BSS's are fully loaded,the new BSS 1120 can share channel 1125C with the 80 MHz BSS 1130. Whenthe new BSS 1120 is fully loaded and existing BSS's 1110, 1130 arelightly loaded, the new BSS 1120 can gain most of the usage of channel1125C with some contention from the existing BSS's 1110, 1130, and someusage of channels 1125A, 1125B, and 1125D.

The third option shown in FIG. 11 for primary channel selection for thenew BSS 1120 is as follows. The primary channel 1125D of the new BSS1120 can be selected to overlap with the primary channel 1115A of the 40MHz existing BSS 1110 and S1 secondary channel 1135B of the existing 80MHz BSS 1130.

In some implementations, the new BSS 1120 can select its primary channelaccording to the first option regardless of the traffic loads of theBSS's.

FIG. 12 shows an example of primary channel selection for a new BSS inan eighth BSS coexistence scenario There is an existing BSS 1220 (e.g.,an IEEE 802.11ac based BSS) that uses a 160 MHz frequency band. Theexisting BSS 1220 is provided by an existing device. There is also a newBSS 1210 (e.g., an IEEE 802.11ac based BSS) 1210 that uses a 160 MHzfrequency band. The frequency bands occupied by the new 160 MHz BSS 1210and the existing 160 MHz BBS 1220 can include two contiguous portions of80 MHz bands, or two discontiguous portions of 80 MHz bands. The 80 MHzfrequency band portion 1215E-H of the new BSS 1210 overlaps with the 80MHz frequency band portion 1225A-D of the existing BSS 1220. Theexisting 160 MHz BSS 1220 includes a primary channel 1225A, a S1secondary channel 1225B, S2 secondary channels 1225C-D, and S3 secondarychannels 1225E-H.

The first option shown in FIG. 12 for primary channel selection for thenew BSS 1210 is as follows. The primary channel (channel 1215A, 1215B,1215C, or 1215D) of the new BSS 1210 can be selected to not overlap withany channels of the existing BSS 1220.

The second option shown in FIG. 12 for primary channel selection for thenew BSS 1210 is as follows. The primary channel 1215E can be selected tooverlap with the primary channel 1225A of the existing BSS 1220.

The third option shown in FIG. 12 for primary channel selection for thenew BSS 1210 is as follows. The primary channel (channel 1215F orchannel 1215G) can be selected to partially overlap with the S2secondary channel 1225C, 1225D of the existing BSS 1220.

The fourth option shown in FIG. 12 for primary channel selection for thenew BSS 1210 is as follows. The primary channel 1215H can be selected tooverlap with the S1 secondary channel 1225B of the existing BSS 1220.

In some implementations, the traffic load on 1225A is high, the new BSS1210 can select the primary channel according to the second option.Otherwise, the new BSS 1210 can select the primary channel according tothe first option.

FIG. 13 shows an example of primary channel selection for a new BSS in aninth BSS coexistence scenario. There is an existing BSS 1320 (e.g., anIEEE 802.11ac based BSS) that uses a 160 MHz frequency band. Theexisting BSS 1320 is provided by an existing device. There is also a newBSS 1310 (e.g., an IEEE 802.11ac based BSS) that uses a 160 MHzfrequency band. The new BSS 1310 is provided by a new device. Thefrequency band occupied by the new 160 MHz BSS 1310 and the existing 160MHz BBS 1320 overlap with each other. Each of the two frequency bandscan include two contiguous portions of 80 MHz bands, or twodiscontiguous portions of 80 MHz bands. The existing 160 MHz BSS 1320includes a primary channel 1325A, a S1 secondary channel 1325B, S2secondary channels 1325C-D, and S3 secondary channels 1325E-H.

The first option shown in FIG. 13 for primary channel selection for thenew BSS 1310 is as follows. The primary channel 1315A of the new BSS1310 can be selected to overlap with the primary channel 1325A of theexisting BSS 1320.

The second option shown in FIG. 13 for primary channel selection for thenew BSS 1310 is as follows. The primary channel 1315B of the new BSS1310 can be selected to overlap with S1 1325B of the existing BSS 1320.

The third option shown in FIG. 13 for primary channel selection for thenew BSS 1310 is as follows. The primary channel (channel 1315C orchannel 1315D) can be selected to partially overlap with either of theS2 secondary channels 1325C, 1325D of the existing BSS 1320.

The fourth option shown in FIG. 13 for primary channel selection for thenew BSS 1310 is as follows. The primary channel (channel 1315E, 1315F,1315G, or 1315H) can be selected to partially overlap with S3 secondarychannels 1325E-H of the existing BSS 1320.

In some implementations, both the new BSS 1310 and the existing BSS 1320are fully loaded, the new BSS 1310 can select the primary channelaccording to the fourth option. When at least one 20 MHz channel in S31425E-H is lightly loaded the new BSS 1310 can select primary channelaccording to the first option.

FIG. 14 shows an example of primary channel selection for a new BSS in atenth BSS coexistence scenario. There are two existing BSS's 1420, 1430(e.g., IEEE 802.11ac based BSS's), each use an 80 MHz frequency band.The two existing BSS's 1420, 1430 are provided by existing devices.There is also a new BSS 1410 (e.g., an IEEE 802.11ac based BSS) thatuses a 160 MHz frequency band, The frequency band occupied by the new160 MHz BSS 1410 can include two contiguous portions of 80 MHz bands, ortwo discontiguous portions of 80 MHz bands, each of the two 80 MHz bandsoverlaps with one of the two 80 MHz used by the two existing 80 MHz BSS1420, 1430. The existing 80 MHz BSS 1420 includes a primary channel1425A, a S1 1425B, and a S2 1325C-D. The existing 80 MHz BSS 1430includes a primary channel 1435A, a S1 secondary channel 1435B, and S2secondary channels 1335C-D.

The first option shown in FIG. 14 for primary channel selection for thenew BSS 1410 is as follows. The primary channel (channel 1415A orchannel 1415G) of the new BSS 1410 can be selected to overlap with oneof the primary channels 1425A, 1435A of the existing BSS's 1420, 1430.

The second option shown in FIG. 14 for primary channel selection for thenew BSS 1410 is as follows. The primary channel (1415B or 1415H) of thenew BSS 1410 can be selected to overlap with one of the S1's 1425B,1435B of the existing BSS's 1420, 1430.

The third option shown in FIG. 14 for primary channel selection for thenew BSS 1410 is as follows. The primary channel (channel 1415C, 1415D,1415E, or 1415F) of the new BSS 1410 can be selected to partiallyoverlap with one of the S2 secondary channels 1425C-D, 1435C-D of theexisting BSS's 1420, 1430.

In some implementations, the new BSS 1410 can select the primary channelaccording to the third option when all BSS's are fully loaded.Otherwise, the new BSS 1410 can select the primary channel according tothe first option.

FIG. 15 shows an example of primary channel selection for a new BSS inan eleventh BSS coexistence scenario. There is an existing BSS 1520(e.g., an IEEE 802.11ac based BSS's) that uses an 80 MHz frequency band.The existing BSS 1520 is provided by an existing device. There is also anew BSS 1510 (e.g., an IEEE 802.11ac based BSS) that uses a 160 MHzfrequency band. The frequency band occupied by the new 160 MHz BSS 1510can include two contiguous portions of 80 MHz bands, or twodiscontiguous portions of 80 MHz bands. The frequency band occupied bythe existing 80 MHz BSS 1520 overlaps with an 80 MHz portion of the 160MHz occupied by the new BSS 1510. The existing 80 MHz BSS 1520 includesa primary channel 1525A, a S1 secondary channel 1525B, and S2 secondarychannels 1525C-D.

The first option shown in FIG. 15 for primary channel selection for thenew BSS 1510 is as follows. The primary channel 1515A of the new BSS1510 can be selected to overlap with the primary channel 1525A of theexisting BSS 1520.

The second option shown in FIG. 15 for primary channel selection for thenew BSS 1510 is as follows. The primary channel 1515B of the new BSS1510 can be selected to overlap with the secondary channel 1525B of theexisting BSS 1520.

The third option shown in FIG. 15 for primary channel selection for thenew BSS 1510 is as follows. The primary channel (1515C or 1515D) of thenew BSS 1510 can be selected to partially overlap with the S2 secondarychannels 1525C, 1525D of the existing BSS 1520.

The fourth option shown in FIG. 15 for primary channel selection for thenew BSS 1510 is as follows. The primary channel (channel 1515E, 1515F,1515G, or 1515H) of the new BSS 1510 can be selected to not overlap withany channels of the existing BSS 1520.

In some implementations, the existing BSS 1520 is lightly loaded, thenew BSS 1510 can select the primary channel according to the fourthoption. Otherwise the new BSS 1510 can select the primary channelaccording to the first option.

A few embodiments have been described in detail above, and variousmodifications are possible. The disclosed subject matter, including thefunctional operations described in this specification, can beimplemented in electronic circuitry, computer hardware, firmware,software, or in combinations of them, such as the structural meansdisclosed in this specification and structural equivalents thereof,including potentially a program operable to cause one or more dataprocessing apparatus to perform the operations described (such as aprogram encoded in a computer-readable medium, which can be a memorydevice, a storage device, a machine-readable storage substrate, or otherphysical, machine-readable medium, or a combination of one or more ofthem).

The term “data processing apparatus” encompasses all apparatus, devices,and machines for processing data, including by way of example aprogrammable processor, a computer, or multiple processors or computers.The apparatus can include, in addition to hardware, code that creates anexecution environment for the computer program in question, e.g., codethat constitutes processor firmware, a protocol stack, a databasemanagement system, an operating system, or a combination of one or moreof them.

A program (also known as a computer program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, or declarative orprocedural languages, and it can be deployed in any form, including as astand alone program or as a module, component, subroutine, or other unitsuitable for use in a computing environment. A program does notnecessarily correspond to a file in a file system. A program can bestored in a portion of a file that holds other programs or data (e.g.,one or more scripts stored in a markup language document), in a singlefile dedicated to the program in question, or in multiple coordinatedfiles (e.g., files that store one or more modules, sub programs, orportions of code). A program can be deployed to be executed on onecomputer or on multiple computers that are located at one site ordistributed across multiple sites and interconnected by a communicationnetwork.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of what may be claimed, but ratheras descriptions of features that may be specific to particularembodiments. Certain features that are described in this specificationin the context of separate embodiments can also be implemented incombination in a single embodiment. Conversely, various features thatare described in the context of a single embodiment can also beimplemented in multiple embodiments separately or in any suitablesubcombination. Moreover, although features may be described above asacting in certain combinations and even initially claimed as such, oneor more features from a claimed combination can in some cases be excisedfrom the combination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. In certain circumstances, multitasking and parallel processingmay be advantageous. Moreover, the separation of various systemcomponents in the embodiments described above should not be understoodas requiring such separation in all embodiments.

1.-24. (canceled)
 25. A method comprising: monitoring, at a firstwireless communication device, a group of wireless channels for signalsfrom one or more second wireless communication devices; identifying,within the group of wireless channels, one or more primary channels onwhich one or more signals are received from the one or more secondwireless communication devices; and selecting, from the group ofwireless channels, a primary channel for the first wirelesscommunication device based on the one or more identified primarychannels and an estimated traffic load associated with at least aportion of the group of wireless channels, wherein selecting the primarychannel for the first wireless communication device comprises: using afirst channel that is separate from the one or more identified primarychannels as the selected primary channel when the estimated traffic loadexceeds a threshold, and using a second channel from the one or moreidentified primary channels as the selected primary channel when theestimated traffic load does not exceed the threshold.
 26. The method ofclaim 25, comprising: measuring one or more channel conditions of theone or more identified primary channels; and calculating one or morebusy-to-idle ratios of the one or more identified primary channels basedon the one or more channel conditions, wherein the estimated trafficload is based on the one or more busy-to-idle ratios.
 27. The method ofclaim 25, wherein the group of wireless channels comprises two frequencyportions, each of the two frequency portions occupying a consecutivefrequency band that is one half of an aggregated frequency bandwidthassociated with the group of wireless channels.
 28. The method of claim27, wherein the selected primary channel is a frequency portion of thetwo frequency portions, the frequency portion having a frequency bandseparate from one or more frequency bands associated with the one ormore identified primary channels.
 29. The method of claim 25, whereinthe one or more signals are received from one second wirelesscommunication device, and wherein the selected primary channel is aprimary channel of the one second communication device on which the oneor more signals are received.
 30. The method of claim 25, wherein atleast a subset of the group of wireless channels does not overlap withwireless channels that are usable by the one or more second wirelesscommunication devices, and wherein the selected channel is a channel inthe at least the subset of the group of wireless channels.
 31. Themethod of claim 25, wherein the one or more second wirelesscommunication devices comprises a device that uses a 20 MHz primarychannel, a 20 MHz secondary channel, and a 40 MHz secondary channel, andwherein the selected channel is a channel in the 40 MHz secondarychannel.
 32. The method of claim 25, wherein the one or more secondwireless communication devices comprises a device that uses a 20 MHzprimary channel, a 20 MHz secondary channel, a 40 MHz secondary channel,and an 80 MHz secondary channel, and wherein the selected channel is achannel in the 80 MHz secondary channel.
 33. An apparatus, comprising:first circuitry configured to monitor a group of wireless channels forsignals from one or more wireless communication devices; and secondcircuitry configured to identify, within the group of wireless channels,one or more primary channels on which one or more signals are receivedfrom the one or more wireless communication devices, and select, fromthe group of wireless channels, a primary channel for a wirelesscommunication based on the one or more identified primary channels andan estimated traffic load associated with at least a portion of thegroup of wireless channels, wherein the selected primary channel is afirst channel that is separate from the one or more identified primarychannels if the estimated traffic load exceeds a threshold, and whereinthe selected primary channel is a second channel from the one or moreidentified primary channels if the estimated traffic load does notexceed the threshold.
 34. The apparatus of claim 33, wherein the secondcircuitry comprises circuitry configured to measure one or more channelconditions of the one or more identified primary channels, and calculateone or more busy-to-idle ratios of the one or more identified primarychannels based on the one or more channel conditions, and wherein theestimated traffic load is based on the one or more busy-to-idle ratios.35. The apparatus of claim 33, wherein the group of wireless channelscomprises two frequency portions, each of the two frequency portionsoccupying a consecutive frequency band that is one half of an aggregatedfrequency bandwidth associated with the group of wireless channels. 36.The apparatus of claim 35, wherein the selected primary channel is afrequency portion of the two frequency portions, the frequency portionhaving a frequency band separate from one or more frequency bandsassociated with the one or more identified primary channels.
 37. Theapparatus of claim 33, wherein the one or more signals are received fromone wireless communication device, and wherein the selected primarychannel is a primary channel of the one wireless communication device onwhich the one or more signals are received.
 38. The apparatus of claim33, wherein at least a subset of the group of wireless channels does notoverlap with wireless channels that are usable by the one or morewireless communication devices, and wherein the selected channel is achannel in the at least the subset of the group of wireless channels.39. The apparatus of claim 33, wherein the one or more wirelesscommunication devices comprises a device that uses a 20 MHz primarychannel, a 20 MHz secondary channel, and a 40 MHz secondary channel, andwherein the selected channel is a channel in the 40 MHz secondarychannel.
 40. The apparatus of claim 33, wherein the one or more wirelesscommunication devices comprises a device that uses a 20 MHz primarychannel, a 20 MHz secondary channel, a 40 MHz secondary channel, and an80 MHz secondary channel, and wherein the selected channel is a channelin the 80 MHz secondary channel.
 41. A system comprising: transceiverelectronics; and processor electronics coupled with the transceiverelectronics, configured to perform operations comprising: monitoring agroup of wireless channels for signals from one or more wirelesscommunication devices; identifying, within the group of wirelesschannels, one or more primary channels on which one or more signals arereceived from the one or more wireless communication devices; andselecting, from the group of wireless channels, a primary channel for awireless communication based on the one or more identified primarychannels and an estimated traffic load associated with at least aportion of the group of wireless channels, wherein selecting the primarychannel for the wireless communication comprises using a first channelthat is separate from the one or more identified primary channels as theselected primary channel when the estimated traffic load exceeds athreshold, and using a second channel from the one or more identifiedprimary channels as the selected primary channel when the estimatedtraffic load does not exceed the threshold.
 42. The system of claim 41,wherein the operations comprise: measuring one or more channelconditions of the one or more identified primary channels; andcalculating one or more busy-to-idle ratios of the one or moreidentified primary channels based on the one or more channel conditions,wherein the estimated traffic load is based on the one or morebusy-to-idle ratios.
 43. The system of claim 41, wherein the group ofwireless channels comprises two frequency portions, each of the twofrequency portions occupying a consecutive frequency band that is onehalf of an aggregated frequency bandwidth associated with the group ofwireless channels.
 44. The system of claim 43, wherein the selectedprimary channel is a frequency portion of the two frequency portions,the frequency portion having a frequency band separate from one or morefrequency bands associated with the one or more identified primarychannels.
 45. The system of claim 41, wherein the one or more signalsare received from one wireless communication device, and wherein theselected primary channel is a primary channel of the one wirelesscommunication device on which the one or more signals are received. 46.The system of claim 41, wherein at least a subset of the group ofwireless channels does not overlap with wireless channels that areusable by the one or more wireless communication devices, and whereinthe selected channel is a channel in the at least the subset of thegroup of wireless channels.
 47. The system of claim 41, wherein the oneor more wireless communication devices comprises a device that uses a 20MHz primary channel, a 20 MHz secondary channel, and a 40 MHz secondarychannel, and wherein the selected channel is a channel in the 40 MHzsecondary channel.
 48. The system of claim 41, wherein the one or morewireless communication devices comprises a device that uses a 20 MHzprimary channel, a 20 MHz secondary channel, a 40 MHz secondary channel,and an 80 MHz secondary channel, and wherein the selected channel is achannel in the 80 MHz secondary channel.